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Updated: Jul 18, 2026

Microfluidics in Assessing Platelet Function
Published on: November 8, 2024
Heparin cofactor II modulates the response to vascular injury
1Division of Hematology, Campus Box 8125, Washington University Medical School, 660 South Euclid Avenue, St. Louis, MO 63110, USA. tollefsen@im.wustl.edu
Abstract:
Heparin cofactor II (HCII) has several biochemical properties that distinguish it from other serpins: (1) it specifically inhibits thrombin; (2) the mechanism of inhibition involves binding of an acidic domain in HCII to thrombin exosite I; and (3) the rate of inhibition increases dramatically in the presence of dermatan sulfate molecules having specific structures. Human studies suggest that high plasma HCII levels are protective against in-stent restenosis and atherosclerosis. Studies with HCII knockout mice directly support the hypothesis that HCII interacts with dermatan sulfate in the arterial wall after endothelial injury and thereby exerts an antithrombotic effect. In addition, HCII deficiency appears to promote neointima formation and atherogenesis in mice. These results suggest that HCII plays a unique and important role in vascular homeostasis.
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